Guitar construction

ABSTRACT

A guitar having a sound box defined by a one piece molded body of bowl shape, and a top board for enclosing the bowl. A neck is attached to the bowl and includes a die cast aluminum alloy defining the fret board and the front of the peg board. This casting is secured to an integrally molded neck block in the body and the weight of the neck is kept low by mounting a plastic back to the casting, the surface contour and texture of the plastic giving the neck a conventional wood grain appearance behind the fret board and peg board.

United States Patent 1191 Martin Oct. 14, 1975 [54] GUITAR CONSTRUCTION3,696,700 10/1972 Berardi 84/293 [75] Inventor. L. Martin, Glastonbury,Primary Examiner joseph w Hartary Assistant ExaminerVit W. Miska l-Assigneel Ovation Instruments, New Attorney, Agent, or Firm-McCormick,Paulding &

Hartford, Conn. H b

[22] Filed: Nov. 8, 1974 [21] Appl. No.: 522,269 [57] ABSTRACT A guitarhavmg a sound box defined by a one piece molded body of bowl shape, anda top board for en- [52] US. Cl. 84/267; 84/291; 84/293 Closing the bowlA neck i attached to the bow] and [51] Int. Cl. GlOD l/OS includes a diecast aluminum alloy defining the fret [58] Field of Search 84/267,291-293 board and the from of the peg board This casting is secured toan integrally molded neck block in the References cued body and theweight of the neck is kept low by mount- UNITED STATES PATENTS ing aplastic back to the casting, the surface contour 2,795,988 6/1957MacCaferri 84/267 and teXwre the Plastic giving the neck a Conven- 3 128 6/19 5 Finch 84/291 tional wood grain appearance behind the fretboard 3,324,755 6/1967 Canonic0..... 84/267 and peg board. 3,474,69710/1969 Laman..... 84/291 3,538,807 11 1970 Francis 84/267 10 Clam, 3Drawlng Flgures Sheet 1 of 2 3,911,778

Patent Oct. 14, 1975 US. Patent Oct. 14, 1975 Sheet 2 of 2 3,911,778

FIG I6 54 GUITAR CONSTRUCTION SUMMARY OF INVENTION This inventionrelates generally to the construction of guitars of the type having ahollow sound box and an upstanding neck attached thereto. Moreparticularly, this invention relates to a composite neck for such aguitar, said neck including a rigid frame member one end of which issecured to a neck block integrally molded in the one piece bowl, or bodyportion of the sound box. A light weight plastic back member is carriedby and faired into the side edges of the neck frame. The frame has afront face which defines the guitar frets, and the neck frame alsosupports the pegs which are adapted to adjustably receive the upper endsof the guitar strings. Thus, the invention permits the frame to be madefrom a structural material such as cast aluminum, while the weight andappearance of the neck is nevertheless kept comparable to theconventional wood neck by black anodizing the front face of the aluminumcasting to simulate ebony for example, and by forming the plastic backwith a contour and external texture to simulate other decorative wood,such as mahogany or the like.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of aguitar constructed in accordance with the present invention.

FIG. 2 is a partially exploded perspective view illustrating the jointprovided between the neck of the guitar illustrated in FIG. 1, a portionof the fret board defining portion of which is broken away, and alsoillustrating the one piece molded bowl which cooperates with the top orsound board (not shown) to define the sound box of the guitarillustrated in FIG. 1.

FIG. 3 is a side elevational view showing the relevant portions of theguitar oriented in a horizontal position.

FIG. 4 is a sectional view generally similar to FIG. 3 but with portionsthereof illustrated in full lines and other portions in section.

FIG. 5 is a sectional view taken generally on the line 55 of FIG. 3.

FIG. 6 is a sectional view taken generally on the line 66 of FIG. 3.

FIG. 7 is a sectional view taken generally on the line 77 of FIG. 3.

FIG. 8 is a bottom view of the rigid neck frame member comprising one-ofthe components of the neck illustrated in assembled relationship inprevious views.

DETAILED DESCRIPTION Turning now to the drawings in greater detail, FIG.1 shows a guitar incorporating the present invention, such a guitarcomprising a sound box indicated generally at 10 and including a onepiece molded generally bowl-shaped body 14 to which is attached agenerally flat top plate or sound board 12. A neck 16 is carried at theupper end of the bowl l4 and the upper end of the neck 16 defines a peghead or peg board 18 to which the upper ends of the various strings 20,20 are conventionally attached by means of adjustable posts. The lowerends of the strings are supported by a bridge 22 directly mounted to thesound board 12 and a sound opening 24 is provided in the top 12inaccordance with conventional practice. The tension in each of thestrings 20, 20 is adapted to be adjusted by use of thumbscrews,indicated generally at 26, 26 one of which is associated with each ofthe strings and each thumbscrew is geared to one of each of the pegsmounted in the peg board structure 18 so as to permit the user to adjustthe tension in the strings of the instrument and thereby tune theinstrument as required. The body 14 of the guitar preferably comprises aone piece molded plastic material which is cast from a polyesterfiberglass sheet molding compound. The body is cast in a two part moldwhich defines the exterior and interior surfaces of this body portion14. Thus, the sound box is defined and derives its bowl shape from anintegrally molded member, which defines the various side walls and givesto the guitar its characteristic upper bout 28 and lower bout 30 withthe characteristic waist 32 provided therebetween. In addition, the rearwall 34 of the bowl body 14 preferably has a rounded bowl-shapedconfiguration such that the rear wall blends smoothly with the sidewalls of the one piece body 14.

One of the two parts of the mold is so shaped that the interior surfaceof the bowl-shaped body 14 forms an integral neck block 36 adjacent thetop of the upper bout 28, and the exterior surface of the bowl body 14is provided with an upwardly opening mortise or groove 38 by properlyshaping the other mold half. This neck block 36 is preferably taperedfrom front to rear so as to be slightly wider in the area where it isjoined to the rear wall 34 of the bowl l4, and this is illustrated inFIG. 7. FIG. 7 also illustrates the configuration of the mortise groove38, and it should also be noted that the neck 16 includes a tenondefining portion 40 which is loosely received in the mortise 38 so as toprovide a void between the tenon 40 and the mortise groove 38. However,the upwardly facing inner wall of the mortise groove 38 is preciselyformed so as to receive a precisely formed cooperating surface on thetenon 40 so that the neck 16 can be secured to the neck block 36 solelyby means of screws 42, 42 as best shown in FIG. 4. As illustrated inFIG. 4 the neck block 36 has a rightwardly facing surface which is alsotapered so as to provide added strength to the relatively massive neckblock 36 and to also permit ready removal of the bowl 14 from its mold.It should perhaps be noted that in the description to follow and in theappended claims, the guitar will be described as it appears in FIG. 1,namely as being disposed in an upright position, for convenience indiscussing the orientation of its various parts.

Turning next to a more detailed description of the unique constructionfor the neck 16 of the guitar illustrated in the drawings, FIG. 4bestillustrates the basic two member construction for this component of theguitar, said neck being there illustrated as including an elongated neckframe member which is fabricated from a relative rigid structuralmaterial such as die cast aluminum to lend the necessary structuralstrength to the neck 16 of the instrument. A plastic back member ismounted to the rear side of the frame member 50 and gives to the neckthe characteristic wood appearance, and convex contour familiar toguitar players generally. This combination of a relatively heavystructural member and a light weight plastic member gives the instrumentthe proper feel or weight distribution. From FIGS. 5 and 6 it will beapparent that the relatively low density plastic material incorporatedinto the the feel and appearance of the back of the neck is derived fromthe relatively light weight plastic portion 60.

In accordance with the present invention, the tenon 40 is definedadjacent the lower end of the neck frame 50 and more particularly at thelower end of a longitudinally extending rib 52 integrally cast in suchneck frame member 50. This rearwardly projecting rib 52 extendingupwardly from said tenon defining portion 40 thereof to the area of thepeg board 18 is best shown in FIG. 4. Thus, the neck frame member 50 hasa generally T-shaped cross sectional configuration, the stem of the Tdefining this rearwardly projecting rib 52.

Still with reference to the configuration of the die cast aluminum neckframe 50 it is a further feature of the present invention that the frontface of such frame member 50 defines the raised frets 54, 54 and moreparticularly defines the fret board itself. These frets are defined inthe form of laterally extending ribs at the front face of the framemember 50 and this fret board defining portion includes a projecting orcantilevered depending leg portion 56 designed to extend over and toabut the front face of the instruments sound board 12 as best shown inFIGS. 3 and 4. This depending portion 56 of the cast frame member 50also serves to cover the mortise and tenon joint connection between theneck 16 and the guitar body portion 14. Thus, the sound board or topplate 12 of the guitars sound box extends between the upper edges of thebowl l4 and the rearwardly facing surface of this depending portion ofthe fret board. Preferably, the area of the front face of the aluminumneck frame 50 which lies between the various frets 54, 54 is anodized toimpart a black color to this portion of the neck which simulates theebony or other wood commonly usedin this area of the more expensiveguitars. Actually, in the process of fabricating the neck the entirefront surface of the aluminum neck frame 50 is anodized, and the area ofthe ribs 54, 54 is ground slightly so as to provide a polished aluminumappearance for the frets themselves.

Still with reference to the aluminum neck frame 50, the upper endportion thereof forms the peg head or peg board area of the neck 16which receives an adjustably supports the upper ends of the strings 20,20 as mentioned previously. As best shown in FIG. 4 this upper endportion 58 of the cast aluminum neck frame 50 is quite thin throughoutits lateral and longitudinal extent, but does define raised bosses 59,59 which bosses serve to provide a suitable support for the posts orpegs 70, 70 utilized to actually support the ends of the guitar strings20, 20. These posts or pegs 70, 70 are rotatable in the peg board bymeans of the thumbscrews 26, 26 through a conventional worm geararrangement indicated generally at 72, 72. These guitar stringsupporting and adjusting components need not be described in detailherein, but it is noted that each is efficiently supported from astructural point of view in the aluminum front face of the neck definedby the cast aluminum neck frame member 50. This portion 58 of thealuminum casting 50 is also given an anodized finish, preferably black,and may have a decorative end portion given it during the casting of themember 50 illustrated generally at 19 in FIG. 1.

Turning next to a more detailed description of the plastic back member60, said member preferably comprises a low density expanded polyurethanefoam material ofthe type sometimes used in the fabrication of furnitureor the like, and it is a further feature ofthe present invention thatthe convex external contour of this back member 60 is given theappearance of natural wood by the presently known technique of providinga silicon bladder in the mold utilized to cast'the aluminum structuralmember 50, which bladder can be itself formed directly on a wood modelso as to take the grain from the model and to impart such grain to themolded polyurethane surface of the back member 60. Some coloring isrequired to be added to the surface of the polyurethane foam material inorder to produce the desired tint in the plastic back member 60, thecolor depending upon whether mahogany is to be simulated or some otherdecorative wood material. It is further noted that in addition toproviding a major portion of the cross sectional area of the neck 16 inthe form of such relatively low density plastic, as described above withreference to FIGS. 5 and 6, it is also a feature of the presentinvention that the neck 16 is provided with a heel portion indicatedgenerally at 62, which heel 62 is also formed primarily of such plasticmaterial and is given the desired shaped as a result of theconfiguration provided for in the mold from which it is formed. Further,the peg board 18 and more particularly the rear portion thereof, alsohas a predominant portion of its cross section defined by said foamfiller material, and here again the result achieved is to provide a neckwhich appears to be fabricated from a wood material rather than the lessexpensive plastic actually utilized.

Still with reference to the unique neck construction provided by thecast aluminum frame member 50 and its associated plastic back member 60,it will be apparent from FIGS. 5 and 6 that the T-shaped configurationfor the frame member 50 offers a relatively large surface area to whichthe plastic foam material of the neck 60 can adhere.,In this connection,it should also be noted that longitudinally extending lands 51, 51 arealso provided adjacent the longitudinally extending lateral edges of thefret board defining portion of the frame 50 and in order to furtherimprove the bond provided between the aluminum and the polyurethane foammaterial of the frame 50 and back member 60 respectively. As illustratedin FIG. 6, the rearwardly projecting stem 52 of the T-shaped framemember 50 is preferably undercut as indicated generally at 53, 53 toprovide the added strength of a mechanical connection between thesemembers 50 and 60. Present practice calls for casting the aluminum sternwithout these recesses 53, 53 and for later machining these recesses togive the rib a generally l-shaped configuration as illustrated best inFIG. 4. Thus, the recesses not only serve to mechanically hold thepolyurethane foam 60 back to the frame 50, but also serves tosignificantly lighten the overall neck 16 and thereby contribute to thestated advantages for this invention.

As best shown in FIG. 8 the cast aluminum neck frame member 50 isslightly tapered in its longitudinal direction so that the upper end issomewhat narrower than the lower end. It is also noted that therearwardly projecting rib 52 is similarly tapered, but that the lowerend of this rib has a slight reverse taper in the area which ultimatelydefines the tenon 40. The depth of this rearwardly projecting rib 52 isbest shown in FIG. 4, but by virtue of a comparison of FIG. 4 with FIG.8 it is noted that the rib 52 has a depth which is approximatelyone-third the width of the fret board throughout a major portion of thelength of such fret board, and

that only in the area of the reverse taper does this rib 52 becomesomewhat deeper, and acutally reaches a depth in the area of such tenondefining portion 40 on the order of the width of such fret board at thatpoint.

Other features of the neck frame member 50 can be seen from the variousviews, especially the rear side view of FIG. 8. The thickness of the peghead defining portion, and that of the fret board defining portion, areminimized as a result of the rib 52 and the lands 51, 51. Further, themarginal edge of these portions of the casting 50 define a bead 57 whichextends peripherally around both these portions. As a result of thesefeatures, the thickness of these portions need only be on the order ofthree thirty-seconds inch, a dimension which provides a light weight forthis aluminum casting, and hence further contributes to the statedadvantages of this invention.

I claim:

1. In a guitar, the combination comprising a hollow sound box includingan integrally molded one piece bowl-shaped body which has a relativelythin wall of subtantially uniform thickness and which also defines athickened portion projecting inwardly of its inside surface to define anintegrally molded neck block adjacent the upper boundary of said body, aneck for attachment to said neck block, said neck including an elongatedneck frame member having a portion adjacent its lower end whichcooperates with said neck block to define a mortise and tenon jointtherebetween, said neck frame member having a portion adjacent its upperend which forms a peg board for receiving the posts to which the guitarstrings are mounted, said neck frame member having an intermediateportion which is of generally T-shaped cross sectional configuration,and a low weight plastic back member carried by a rearwardly projectingrib defined by the stem of the T- shaped frame, said plastic back memberbeing molded to have a generally convex external contour and the opposedlongitudinally extending lateral edges of said back member being fairedinto the laterally opposed longitudinally extending side edges of theT-shaped neck frame member.

2. In a guitar the combination as set forth in claim 1 wherein said neckframe member has a generally flat front face defining the fret board ofthe guitar, said front face having raised laterally extending ribs atspaced longitudinal locations defining the frets for the guitar, andsaid fret board defining portion including a lower end extending infront of the mortise and tenon joint, and said sound box including a topwhich covers the bowl-shaped body and which top has a portion extendingbetween the bowl and the underside of said lower fret board defining endof said neck frame member.

3. In a guitar the combination as set forth in claim 1 wherein saidbowl-shaped body is integrally molded from a rigid plastic material, andwherein said neck frame member is integrally molded from a die castmetal material.

4. In a guitar the combination as set forth in claim 2 wherein saidbowl-shaped body is integrally molded from a rigid plastic material, andwherein said neck frame member is integrally molded from a die castmetal material, and said plastic back member comprises a low densityexpanded polyurethane foam material with said convex external contourhaving the appearance of the natural wood, and T-shaped neck frame beingfabricated from an aluminum alloy and said front face thereof beinganodized, said fret defining ribs being finished to provide a colorcontrast between the anodized face of the fret board and said frets.

5. In a guitar the combination as set forth in claim 4 wherein saidplastic filler material is molded directly to the back side of saidT-shaped frame member, said rearwardly projecting rib of said T-shapedframe member having opposed laterally outwardly projecting flanges toprovide a generally I-shaped cross section for said rib.

6. In a guitar the combination as set forth in claim 5 wherein said rearside of said T-shaped frame member further includes longitudinallyextending rearwardly projecting flanges spaced just inwardly of saidlaterally opposed side edges of said neck frame member.

7. In a guitar the combination as set forth in claim 4 wherein saidpolyurethane foam filled portion of said neck includes a portion behindsaid aluminum alloy peg board to provide a massive wood appearance tothe upper end of the neck without significantly adding to the overallweight of the guitar neck.

8. In a guitar the combination as set forth in claim 7 wherein saidrearwardly projecting rib of said T-shaped frame member extendsdownwardly to define said tenon at its lower end, said rib having adepth which is approximately one-third the lateral width of the fretboard defining portion of said neck frame member except for that portionof said rib defining said tenon, which tenon defining portion of saidrib has a depth which is approximately equal to the width of the fretboard defining portion.

9. In a guitar the combination as set forth in claim 8 wherein saidpolyurethane foam filled portion of said neck includes a heel portionabove and behind said tenon defining portion of said rib, which heelportion hides said rib and covers said mortise and tenon joint.

10. In a guitar the combination as set forth in claim 9 wherein saidtenon defining rib portion has a lower face which mates with an innerface on the mortise defining portion of said neck block, and at leastone screw extending upwardly through an opening in said neck block andthreadably received in said tenon defining rib.

1. In a guitar, the combination comprising a hollow sound box includingan integrally molded one piece bowl-shaped body which has a relativelythin wall of subtantially uniform thickness and which also defines athickened portion projecting inwardly of its inside surface to define anintegrally molded neck block adjacent the upper boundary of said body, aneck for attachment to said neck block, said neck including an elongatedneck frame member having a portion adjacent its lower end whichcooperates with said neck block to define a mortise and tenon jointtherebetween, said neck frame member having a portion adjacent its upperend which forms a peg board for receiving the posts to which the guitarstrings are mounted, said neck frame member having an intermediateportion which is of generally T-shaped cross sectional configuration,and a low weight plastic back member carried by a rearwardly projectingrib defined by the stem of the T-shaped frame, said plastic back memberbeing molded to have a generally convex external contour and the opposedlongitudinally extending lateral edges of said back member being fairedinto the laterally opposed longitudinally extending side edges of theTshaped neck frame member.
 2. In a guitar the combination as set forthin claim 1 wherein said neck frame member has a generally flat frontface defining the fret board of the guitar, said front face havingraised laterally extending ribs at spaced longitudinal locationsdefining the frets for the guitar, and said fret board defining portionincluding a lower end extending in front of the mortise and tenon joint,and said sound box including a top which covers the bowl-shaped body andwhich top has a portion extending between the bowl and the underside ofsaid lower fret board defining end of said neck frame member.
 3. In aguitar the combination as set forth in claim 1 wherein said bowl-shapedbody is integrally molded from a rigid plastic material, and whereinsaid neck frame member is integrally molded from a die cast metalmaterial.
 4. In a guitar the combination as set forth in claim 2 whereinsaid bowl-shaped body is integrally molded from a rigid plasticmaterial, and wherein said neck frame member is integrally molded from adie cast metal material, and said plastic back member comprises a lowdensity expanded polyurethane foam material with said convex externalcontour having the appearance of the natural wood, and T-shaped neckframe being fabricated from an aluminum alloy and said front facethereof being anodized, said fret defining ribs being finished toprovide a color contrast between the anodized face of the fret board andsaid frets.
 5. In a guitar the combination as set forth in claim 4wherein said plastic filler material is molded directly to the back sideof said T-shaped frame member, said rearwardly projecting rib of saidT-shaped frame member having opposed laterally outwardly projectingflanges to provide a generally I-shaped cross section for said rib. 6.In a guitar the combination as set forth in claim 5 wherein said rearside of said T-shaped frame member further includes longitudinallyextending rearwardly projecting flanges spaced just inwardly of saidlaterally opposed side edges of said neck frame member.
 7. In a guitarthe combination as set forth in claim 4 wherein said polyurethane foamfilled portion of said neck includes a portion behind said aluminumalloy peg board to provide a massive wood appearance to the upper end ofthe neck without significantly adding to the overall weight of theguitar neck.
 8. In a guitar the combination as set forth in claim 7wherein said rearwardly projecting rib of said T-shaped frame memberextends downwardly to define said tenon at its lower end, said ribhaving a depth which is approximately one-third the lateral width of thefret board defining portion of said neck frame member except for thatportion of said rib defining said tenon, which tenon defining portion ofsaid rib has a depth which is approximately equal to the width of thefret board defining portion.
 9. In a guitar the combination as set forthin claim 8 wherein said polyurethane foam filled portion of said neckincludes a heel portion above and behind said tenon defining portion ofsaid rib, which heel portion hides said rib and covers said mortise andtenon joint.
 10. In a guitar the combination as set forth in claim 9wherein said tenon defining rib portion has a lower face which mateswith an inner face on the mortise defining portion of said neck block,and at least one screw extending upwardly through an opening in saidneck block and threadably received in said tenon defining rib.